WinCC Flexible 2008 Compatibility with TP 277 6" HMI Transfer

1. Overview

The SIMATIC TP 277 6" touch panel with order number 6AV6 643-0AA01-1AX0 is one of the most commonly deployed mid-range HMIs from the Siemens 270/277 panel generation. It uses WinCC Flexible (not WinCC Comfort / TIA Portal) as its configuration environment, which makes the engineering software selection non-trivial once the panel is already installed in the field. This reference resolves the recurring question: Is WinCC Flexible 2008 compatible with the TP 277 6"? and the secondary question: Can a PC Adapter (MPI/DP) cable be used to upload the project from the panel?

The short answer is: yes to both, but with specific constraints. WinCC Flexible 2008 (any SP from SP1 through SP5) supports the TP 277 family across all display sizes (4", 6", 8", 10"). The PC Adapter USB A2 (MPI/DP) supports point-to-point transfer when the panel's RS-422/DP port is configured for MPI or PROFIBUS, and backtransfer is enabled on the panel side and was enabled at compile time on the engineering side.

2. Hardware Identification: TP 277 6" MLFB Decoding

Before resolving any compatibility question, confirm the panel order number (MLFB - Machine-Readable Product Code). The 6AV6 643-0AA01-1AX0 breakdown:

The TP 277 6" ships with a single configuration interface: an RS-422 / MPI / PROFIBUS DP combined port (sub-D female, 9-pin). There is no Ethernet, no USB host, and no PROFINET on this part number. The 10" variant (6AV6 643-0BA01-1AX0) and 8" variant (6AV6 643-0AE01-1AX0) carry the same interface layout.

3. WinCC Flexible Compatibility Matrix

WinCC Flexible engineering software supports a defined matrix of panels. The TP 277 series is supported from WinCC Flexible 2004 onward, with full functionality delivered in WinCC Flexible 2005 and later. The following matrix lists the relevant service packs:

When the source panel project was originally compiled with WinCC Flexible 2005, you can still load it with WinCC Flexible 2008 SP5. When uploading (backtransferring), the project is restored in the same source-format version as it was compiled; WinCC Flexible 2008 SP5 can convert it on import.

3.1 Engineering PC Requirements (WinCC Flexible 2008 SP5)

• OS: Windows XP Professional SP3, Windows Vista Business SP2, Windows 7 Professional/Ultimate 32-bit (SP1), Windows Server 2003 SP2 / 2008 R2
• CPU: 1.6 GHz minimum, 2.4 GHz recommended
• RAM: 1 GB minimum (32-bit OS); 2 GB recommended
• Disk: 3 GB free for installation
• Display: 1024 x 768 minimum, 1280 x 1024 recommended

4. PC Adapter (MPI/DP) Cable: Selection and Pinout

The PC Adapter couples the engineering PC to the TP 277 panel via MPI or PROFIBUS DP. Two cable generations are commonly encountered in the field:

* The 6ES7 972-0CB20-0XA0 PC Adapter USB A2 includes signed drivers for Windows 7, 8.1, and 10. Windows 10 is officially not supported by WinCC Flexible, but the cable drivers alone install cleanly on Windows 10 when used for STEP 7 or TIA Portal transfer.

4.1 Cable Pinout (RS-422 Side, to Panel)

The PC Adapter terminates in a sub-D 9-pin male connector that mates with the panel's RS-422 / MPI / DP port. The pinout is the standard PROFIBUS DP connector assignment:

5. Transfer Options on TP 277

The TP 277 supports four transfer channels:

1. Serial (point-to-point, RS-422 null-modem) - legacy, used with the serial PC/PPI cable or serial PC Adapter.
2. MPI - 187.5 kbps default, address 1 by default on the panel.
3. PROFIBUS DP - up to 12 Mbps, address 1 by default.
4. Ethernet (only on -1AX1 suffix panels) - not applicable to 6AV6 643-0AA01-1AX0.

For the 6AV6 643-0AA01-1AX0 TP 277 6", options 1-3 are available. The most common field workflow is MPI at 187.5 kbps because that rate is universally supported by the PC Adapter USB regardless of driver age.

6. Engineering Software Configuration (WinCC Flexible)

6.1 Set the Transfer Channel

1. Open the WinCC Flexible 2008 project.
2. In the project tree, right-click the panel (TP 277 6") and select Properties.
3. Open the Transfer tab.
4. Set Channel 1 to MPI (or PROFIBUS DP, depending on the cable).
5. Set the MPI/DP address of the panel (default 1).
6. Set the baud rate (default 187.5 kbps).
7. Check Enable transfer.

6.2 Set the PG/PC Interface on the Engineering PC

1. Open Start > SIMATIC > PG/PC Interface (or Set PG/PC Interface from the WinCC Flexible toolbar).
2. Set the access point S7ONLINE (or WinCC Flexible) to PC Adapter (MPI) or PC Adapter (PROFIBUS).
3. Click Properties and verify the cable is detected. The COM port is virtualized by the adapter driver.
4. Set the PC Adapter's MPI address (default 0).
5. Set the transmission rate to 187.5 kbps.
6. Confirm with OK and close the PG/PC Interface dialog.

7. Backtransfer / Upload Procedure

Unlike a download (compile > transfer > panel), the backtransfer retrieves the project source from the panel back to the engineering PC. This requires two enabling conditions.

7.1 Verify Backtransfer Is Enabled at Compile Time

1. Open the WinCC Flexible project.
2. Right-click the TP 277 6" device > Properties.
3. Open the Transfer tab.
4. Under Settings for the transfer, check Enable backtransfer.
5. Recompile and re-download the project so the source is committed to the panel flash with the backtransfer flag set.

7.2 Verify Backtransfer Is Enabled on the Panel

1. On the panel, enter Control Panel (via the corresponding button in the loader).
2. Open OP Properties > Transfer.
3. Check Enable backtransfer (this is the runtime-side switch).
4. Press OK and confirm the panel restart prompt.

7.3 Execute the Upload from WinCC Flexible

1. In WinCC Flexible 2008, select Project > Transfer > Backtransfer (menu path varies slightly between SP levels; in SP4/SP5 it is Online > Backtransfer).
2. Select the channel (MPI or PROFIBUS) and confirm.
3. The status dialog shows the panel discovered at MPI address 1, the connection establishing, the file listing, and the upload progress.
4. Choose a destination folder on the PC for the recovered project source.
5. Click Start. The transfer typically takes 30 s - 5 min depending on project size.

After upload, the recovered project opens in WinCC Flexible and can be edited, recompiled, and re-downloaded. Note that recovered projects sometimes carry a flag indicating the compilation environment; if the original was compiled with WinCC Flexible 2005, the recovered project opens in that version's UI elements unless converted.

8. Direct Download Procedure (Binary)

When no backtransfer is needed (the panel needs only a runtime image), use the standard download path:

1. Connect the PC Adapter between the engineering PC and the panel MPI/DP port.
2. Set the PG/PC interface as described in Section 6.2.
3. On the panel, open Control Panel > Transfer. The panel enters transfer mode.
4. In WinCC Flexible, select Project > Transfer > Transfer (or click the transfer toolbar icon).
5. Select MPI/DP as the channel. WinCC Flexible scans MPI address 1 by default.
6. Click Transfer. The compiled runtime (.fwx) is sent and the panel reboots automatically.

Typical transfer time: 30-90 s for a typical TP 277 6" project (1-4 MB runtime image) at 187.5 kbps. At 1.5 Mbps, this drops to under 10 s.

9. Troubleshooting Matrix

10. Verification Checklist

1. Confirm panel MLFB is 6AV6 643-0AA01-1AX0 (read the side label or Control Panel > OP Properties).
2. Confirm panel firmware version is compatible with the runtime image generated by the WinCC Flexible SP installed on the engineering PC.
3. Confirm PG/PC interface is set to PC Adapter (MPI) at 187.5 kbps, address 0.
4. Confirm panel MPI address is 1 (default) and baud rate is 187.5 kbps.
5. Confirm PC Adapter USB A2 driver installs cleanly and the cable is detected in Device Manager.
6. Confirm transfer is enabled in Control Panel > Transfer on the panel.
7. Confirm backtransfer flag is set on both project (compile) and panel (runtime) when an upload is needed.
8. After transfer, verify the panel boots into the project and tag connections to the PLC are healthy (look at the status indicators / connection diagnostics).

11. Migration Considerations

When the TP 277 6" reaches end of life or spares become scarce, migrate to:

• KTP400 Comfort (4.3") with 6AV2 124-1DC01-0AX0 for the smallest footprint.
• TP700 Comfort (7") with 6AV2 124-1GC01-0AX0 for a like-for-like 6"-class replacement with PROFINET.

Migration requires WinCC Comfort (TIA Portal) and a project converter. WinCC Flexible 2008 SP5 projects can be migrated directly through the TIA Portal V13 - V17 migration tool. The migration preserves screen layout, tag names, alarm classes, and most scripts, but PLC tag pointers may need re-binding if the underlying S7 program has changed.

12. Reference Documentation

• Siemens Support Entry 10805567 - Compatibility and transfer options for SIMATIC Panels
• Siemens Industry Online Support (overall)